Architecture of Planetary Systems Predicted from Protoplanetary Disks Observed with ALMA. II. Evolution Outcomes and Dynamical Stability

Abstract

Recent ALMA observations on disk substructures suggest the presence of embedded protoplanets in a large number of disks. The primordial configurations of these planetary systems can be deduced from the morphology of the disk substructure and serve as initial conditions for numerical investigation of their future evolution. Starting from the initial configurations of 12 multiplanetary systems deduced from ALMA disks, we carried out two-stage N-body simulation to investigate the evolution of the planetary systems at the disk stage, as well as the long-term orbital stability after the disk dispersal. At the disk stage, our simulation includes both the orbital migration and pebble/gas accretion effects. We found that a variety of planetary systems are produced and can be categorized into distant giant planets, Jupiter-like planets, Neptune-like planets, and distant small planets. We found that the disk-stage evolution and the final configurations are sensitive to both the initial mass assignments and viscosity. After the disk stage, we implement only mutual gravity between star and planets and introduce stochastic perturbative forces. All systems are integrated for up to 10 Gyr to test their orbital stability. Most planetary systems are found to be stable for at least 10 Gyr, with perturbative force in a reasonable range. Our result implies that a strong perturbation source such as stellar flybys is required to drive the planetary system unstable. We discuss the implications of our results on both the disk and planet observation, which may be confirmed by the next-generation telescopes such as JWST and ngVLA.